The 1990 United States Census estimated that there were approximately 36 million women age 50 or older. This number is likely to rise with the next census. Based on studies conducted in the early 1990s, prevalence estimates for the use of hormone replacement therapy by menopausal women range from 10% to 71% in specific geographic regions of the United States. A recent national survey estimates the prevalence of use to be around 37%. The forms of postmenopausal therapy available to these women are changing quickly and older regimens are being used in new ways. Hormone replacement therapy and other post-menopausal therapy and other post-menopausal prescriptions (e.g., drugs to prevent and treat osteoporosis and selective estrogen receptor modulators) are being used to alleviate menopausal symptoms and, in some cases, to prevent some of the diseases associated with the post-menopausal state. But, hormone replacement therapy and other forms of postmenopausal therapy remain controversial with respect to their long term risks and benefits. This fat- changing atmosphere and continued medical uncertainty make counseling menopausal patients a complex process. Therefore it is important to follow current medical practice and beliefs with respect to physician counseling about these therapies as well as to learn the extent to which preventive and therapeutic prescriptions are being given at women at and after the menopause. Recent national studies of physician counseling and prescription trends are lacking. I will use the National Prescription Audit (NPA) and the National Disease and Therapeutic Index (NDTI) to describe the types and percentages of actual, dispensed prescriptions for both hormonal and non-hormonal (e.g. osteoporosis drugs and selective estrogen receptor modulators) postmenopausal therapies during the period 1993 to 1999. The NPA projects actual, dispensed prescriptions in the United States. The NDTI database will be used to evaluate the reasons physicians choose certain menopausal therapies, the types of patients receiving these therapies, and the specific regimens being prescribed. A study of geographic variations in prescribing practices using both datasets will reveal whether particular regions of the country are adopting newer regimens faster than others or if there is geographic variation in the prescription of any of the forms of postmenopausal therapy. These data will also be used to evaluate the reasons for prescription of these drugs (therapeutic versus preventive) and the underlying patient, physician and geographic characteristics associated with these prescriptions. Secondly, I will conduct a survey of US women physicians who are involved in the direct patient care of women over the age of 45. A detailed baseline questionnaire will provide information about the physician's current health status and previous and family medical history as well as menopausal status, including use of postmenopausal therapy. This information will be compared with physician to a follow-up survey that evaluat4es their prescribing practices for postmenopausal therapy, including how they counsel patients who are at high risk for breast cancer, heart disease of osteoporosis.